A system, method and apparatus for mixer phase response measurement comprises a vector network analyzer connectable to a device under test, an additional device connected to the analyzer the additional device configured to have an equal phase response to that of the device under test, a local oscillator connected to the device under test and the additional device, a series of switches connecting the device under test and the additional device to a vector voltmeter, and a reference generator connected to the vector voltmeter.

Techniques for estimating a phase relation between a first binary signal and a second binary signal, in particular to a clock-to-data phase detection in double-data-rate signals. The binary signals may include both rising and falling signal edges. Techniques may include determining a first and second signal edge for the first binary signal and comparing the signal edges of the first binary signal to one or more signal edges of the second binary signal, then performing one or more calculations based on the comparisons. The phase relation between the first binary signal and the second binary signal may be determined based on the one or more calculations.

A system is provided for use with an optical input signal for detecting a phase difference between a first RF signal having a first phase and a second RF signal having a second phase. The system includes and optical waveguide, a first optical resonant cavity, a first RF receiver, a second optical resonant cavity and a second RF receiver. The optical resonant cavities include a non-linear electro-optical material. The first RF receiver affects the first non-linear electro-optical material of the first optical resonant cavity. The second RF receiver affects the second non-linear electro-optical material of first optical resonant cavity. The optical waveguide outputs an optical output signal based on the optical input signal as modified by the first optical resonant cavity as affected by the first RF receiver receiving the first RF signal and as modified by the second optical resonant cavity as affected by the second RF receiver.

A differential phase and amplitude detector circuit is presented. Two source follower circuits respectively based on NMOS and PMOS transistors are used to charge and discharge a sampling capacitor asymmetrically to provide a measurement of phase and/or amplitude difference between two signals of a substantially same frequency. The measurement can be made in one cycle, with the charging of the sampling capacitor performed during a first half cycle where a voltage difference between the two signals is positive, and the discharging during a second half cycle where a voltage difference between the two signals is negative. Biasing of the two source follower circuits enable an excess current flow between the two transistors of the two source follower circuits beyond a biasing current of the transistors to charge the sampling capacitor during the first half cycle, and disable the excess current flow between the two transistors during the second half cycle.

A monitoring system is provided for correcting phase angle errors using an accurate current sensor such as a current transformer, or Rogowski coil. Using an accurate source of time and communication, such as a cellular or mesh radio, this correction can then be applied across a fleet of sensors within a range (governed by wave propagation speed of electricity) and between transformers.

A system, method and apparatus for mixer phase response measurement comprises a vector network analyzer connectable to a device under test, an additional device connected to the analyzer the additional device configured to have an equal phase response to that of the device under test, a local oscillator connected to the device under test and the additional device, a series of switches connecting the device under test and the additional device to a vector voltmeter, and a reference generator connected to the vector voltmeter.

In one embodiment, a phase detection circuit includes a current signal input to receive a current signal indicative of a current amplitude of an RF signal and a voltage signal input to receive a voltage signal indicative of a voltage amplitude of the RF signal. A high-pass filter and a low-pass filter are each configured to filter one of (i) the current signal from the current signal input or (ii) the voltage signal from the voltage signal input, wherein the high-pass filter and the low-pass filter collectively cause a substantially 90 degree offset between a phase angle of the current signal and a phase angle of the voltage signal. A phase difference circuit receives the filtered current signal and the filtered voltage signal to determine a phase angle difference between the current signal and the voltage signal.

A differential phase and amplitude detector circuit is presented. Two source follower circuits respectively based on NMOS and PMOS transistors are used to charge and discharge a sampling capacitor asymmetrically to provide a measurement of phase and/or amplitude difference between two signals of a substantially same frequency. The measurement can be made in one cycle, with the charging of the sampling capacitor performed during a first half cycle where a voltage difference between the two signals is positive, and the discharging during a second half cycle where a voltage difference between the two signals is negative. Biasing of the two source follower circuits enable an excess current flow between the two transistors of the two source follower circuits beyond a biasing current of the transistors to charge the sampling capacitor during the first half cycle, and disable the excess current flow between the two transistors during the second half cycle.

Phase detector circuitry includes oscillator circuitry, edge detection and correction circuitry, sampler circuitry, and adder circuitry. The oscillator circuitry is configured to provide a sawtooth oscillator signal. The edge detection and correction circuitry is configured to receive an in-phase signal and a quadrature signal, provide an edge detection signal during each edge of the in-phase signal and the quadrature signal, and provide an edge correction signal based on whether the edge is in the in-phase signal or the quadrature signal and whether the edge is a rising edge or a falling edge. The sampler circuitry is configured to sample the sawtooth oscillator signal in response to the edge detection signal. The adder circuitry is configured to subtract the edge correction signal from the sampled sawtooth oscillator signal to provide a phase estimate signal.

A system is provided for use with an optical input signal for detecting a phase difference between a first RF signal having a first phase and a second RF signal having a second phase. The system includes and optical waveguide, a first optical resonant cavity, a first RF receiver, a second optical resonant cavity and a second RF receiver. The optical resonant cavities include a non-linear electro-optical material. The first RF receiver affects the first non-linear electro-optical material of the first optical resonant cavity. The second RF receiver affects the second non-linear electro-optical material of first optical resonant cavity. The optical waveguide outputs an optical output signal based on the optical input signal as modified by the first optical resonant cavity as affected by the first RF receiver receiving the first RF signal and as modified by the second optical resonant cavity as affected by the second RF receiver.